Modulation of pain sensation by stress-related testosterone and cortisol.

Stress increases cortisol and decreases testosterone. It is not known whether pain is affected by stress-related testosterone. Therefore, we investigated whether stress can affect pain perception by decreasing testosterone and increasing cortisol. Pain thresholds, pain and anxiety ratings and salivary testosterone and cortisol levels were measured in 46 healthy men during resting and stressful conditions. Pain was induced by electrical stimulation. Stress was induced by having participants perform a medical test. Stress significantly increased anxiety ratings and salivary cortisol levels, but decreased salivary testosterone levels. Stress also increased pain ratings and decreased pain thresholds. During stress, cortisol levels were negatively correlated with pain thresholds and testosterone levels were positively correlated with pain thresholds. Results indicated that testosterone can decrease and cortisol can increase pain induced by electrical stimulation, suggesting that acute clinical pain may be relieved by controlling stress and managing consequent stress-related testosterone and cortisol.

Secondary prophylaxis treatment versus on-demand treatment for patients with severe haemophilia A: comparisons of cost and outcomes in Taiwan.

This study compared secondary prophylaxis treatment with on-demand treatment for severe haemophilia A in Taiwan. Fifty patients from one medical centre were evaluated over a 5-year period. Differences in annual bleed rates and factor VIII (FVIII) utilization were assessed between patients receiving secondary prophylaxis and patients receiving FVIII concentrates on-demand. Results were then used as inputs in a pharmacoeconomic model to predict outcomes of future haemophilia therapy strategies in Taiwan. The median annual number of total bleeding episodes was significantly lower in the 13 (26%) patients who received secondary prophylaxis than in the 37 patients who received FVIII on-demand (7.76 vs. 31.91, P < 0.0001). The between-group difference in median annual factor VIII utilization was statistically significant (1824.41 IU kg(-1) for the prophylaxis group and 1324.81 IU kg(-1) for the on-demand group, P < 0.01). It was estimated that approximately $2 million (USD) per year would be added to the cost of treatment by having all severe haemophilia A patients in Taiwan receive secondary prophylaxis instead of on-demand therapy while 12,566 bleeding will be prevented. It is recommended that National Health Insurance officials utilize these data to evaluate the benefits of enhanced treatment strategies and before making substantial policy changes to haemophilia care in Taiwan.

A DEAB-sensitive aldehyde dehydrogenase regulates hematopoietic stem and progenitor cells development during primitive hematopoiesis in zebrafish embryos.

Although aldehyde dehydrogenase (ALDH) activity has become a surrogate of hematopoietic stem and progenitor cells (HSPCs), its function during hematopoiesis was unclear. Here, we examined its role in zebrafish hematopoiesis based on pharmacological inhibition and morpholino (MO) knockdown. Zebrafish embryos were treated with diethylaminobenzaldehyde (DEAB, 1 µmol/l) between 0- and 48 hour-post-fertilization (hpf). MOs targeting aldhs were injected between 1 and 4-cell stage. The effects on hematopoiesis were evaluated at different stages. DEAB treatment between 0 and 18 hpf increased gene expression associated with HSPC (scl, lmo2), erythropoiesis (gata1, α- and ß-eHb) and myelopoiesis (spi1) as well as gfp(+) cells in dissociated Tg(gata1:gfp) embryos. The effects were ameliorated by all-trans retinoic acid (1 nmol/l). Definitive hematopoiesis and the erythromyeloid precursors were unaffected. In all, 14 out of 15 zebrafish aldhs were detectable by reverse transcription PCR in 18 hpf embryos, of which only aldh1a2 and aldh16a1 were expressed in sites pertinent to hematopoiesis. Molecular targeting by MOs was demonstrated for 15 aldhs, but none of them, even in combined aldh1a2 and aldh1a3 knockdown, recapitulated the hematopoietic expansion in DEAB-treated embryos. In conclusion, DEAB expands HSPC population during primitive hematopoiesis through inhibition of aldh and retinoic acid synthesis. The specific aldh isoform(s) remains to be determined.

The role of survivin2 in primitive hematopoiesis during zebrafish development.

Survivin is an inhibitor of apoptosis and its role in embryonic development is not completely understood. In zebrafish, survivin undergoes gene duplication. Survivin1 (sur1) has been shown to mediate angiogenesis but not hematopoiesis. In this study, we examined survivin2 (sur2) with particular reference to its role in primitive hematopoiesis during zebrafish development. sur2 was expressed predominantly in the intermediate cell mass (ICM, site of primitive hematopoiesis). Morpholino (MO) targeting at intron1-exon2 junction of sur2 significantly reduced green fluorescent protein(+) (erythroid) cell population in transgenic Tg (gata1:gfp) embryos at 18 h post-fertilization (h.p.f.; wild type: 4.49+/-0.15%; Sur2(MO) embryos: 2.22+/-0.12%, P=0.02). Molecular targeting was confirmed by reverse transcription-PCR and MO specificity by successful sur2 mRNA rescue. sur2 MO also downregulated genes associated with hematopoietic stem cells (scl, lmo2), erythroid (gata1, alpha- and beta-embryonic hemoglobins) as well as early (pu.1) and late (mpo, l-plastin) myelomonocytic lineages at 12 and 18 h.p.f. This was associated with an increase in apoptosis in the ICM and alteration of cell-cycle status of erythroid cells. Both effects were caspase dependent. In conclusion, sur2 is important in maintaining hematopoietic stem and lineage committed cells during zebrafish development, by virtue of its antiapoptotic activity in a caspase dependent and cell autonomous fashion.

Synthesis, antiplatelet and vasorelaxing effects of monooxygenated flavones and flavonoxypropanolamines.

A series of flavones and flavonoxypropanolamines were synthesized and tested in-vitro for their ability to inhibit aggregation of washed rabbit platelets and human platelet-rich plasma (PRP), and for vasoconstriction of rat thoracic aorta. The various substituted positions of the hydroxyl group in flavone ring B and the various oxypropanolamine side chains substituted at position C-2' of flavone modified the antiplatelet effects. All the compounds tested in human PRP showed significant inhibition of secondary aggregation induced by adrenaline (epinephrine), suggesting that the antiplatelet effect of these compounds is mainly due to an inhibitory effect on thromboxane formation. Compounds 11 and 12 also had potent vasorelaxant effects in rat thoracic aorta. Phenylephrine- and high-K+-induced 45Ca2+ influx in aorta were both inhibited by the selected compound 11. This result indicates that the inhibitory effect of 11 on the contractile response caused by high-K+ medium and noradrenaline (norepinephrine) in rat thoracic aorta is mainly due to inhibition of Ca2+ influx through both voltage-dependent and receptor-operated Ca2+ channels.

New lanostanoids of Ganoderma tsugae.

Three new compounds, (24R, S)-3alpha-acetoxy-24-hydroxy-5alpha-lanosta-8,25-di en-21-oic acid, named tsugaric acid C (1); 3alpha-acetoxy-5alpha-lanosta-8, 24-diene-21-O-beta-D-xyloside, named tsugarioside B (2); and 3alpha-acetoxy-(Z)-24-methyl-5alpha-lanosta-8,23,25-tr ien-21-oic acid ester beta-D-xyloside, named tsugarioside C (3), and a mixture of two known steroids were isolated from the fruit bodies of Ganoderma tsugae. The structures of 1-3 were determined by spectral and chemical methods. The cytotoxic activity of the lanostanoid constituents of this fungus was evaluated against several different cancer cell lines.

Synthesis and cytotoxic effect of 1,3-dihydroxy-9,10-anthraquinone derivatives.

1,3-Dihydroxy-9,10-anthraquinone (4) was reacted with epichlorohydrin or 1,omega-dibromo-alkane to yield 1-hydroxy-3-(2,3-epoxypropoxy)-9,10-anthraquinone (5) and 1-hydroxy-3-(3-chloro-2-hydroxypropoxy)-9,10-anthraquinone (6) or 1-hydroxy-3-(omega-bromoalkoxy)-9,10-anthraquinone. Ring-opening of the epoxide (5) or 1-hydroxy-3-(omega-bromoalkoxy)-9,10-anthraquinones with appropriate amines, afforded various 1-hydroxy-3-(3-alkylamino-2-hydroxypropoxy)-9,10-anthraquinones. The synthetic compounds were tested in vitro inhibition of human T-24, Hep 3B, Hep G2, SiHa, HT-3, PLC/PRF/5 and 212 cells. Almost all compounds showed significant inhibitory activity against several different cancer cell lines. Structure-activity analysis indicated epoxidation of the hydroxyanthraquinone increased cytotoxicity against tumour cells, but ring-opening of the epoxide group with amine did not enhance the cytotoxic activity. The phosphatidylserine (PS) externalization and DNA fragmentation in SiHa cells were significantly observed after 48 h incubation with selected compound 19. The results show that 19 cause cell death by apoptosis.

A new chalcone, xanthones, and a xanthonolignoid from Hypericum geminiflorum.

A new prenyl chalcone, gemichalcone C (1), was isolated from the heartwood and root of Hypericum geminiflorum. Three new xanthones-6, 7-dihyroxy-1,3-dimethoxyxanthone (2), 4-hydroxy-1, 2-dimethoxyxanthone (3), and gemixanthone A (4)-and four known xanthones were isolated from the leaves and stems of the same plant.

A novel triterpenoid of Garcinia subelliptica.

A novel lupane triterpene, 3beta-hydroxy-20,29,30-trinorlupan-19-one, garcinielliptone (1), has been isolated from the seeds of Garcinia subelliptica.

A new flavone C-glycoside and antiplatelet and vasorelaxing flavones from Gentiana arisanensis.

A new flavone C-glycoside, isovitexin 6"-O-glucoside (1), and three known flavonoids, quercetin, isovitexin, and luteolin-7-O-beta-D-glucoside, have been further isolated from the whole plant of Gentiana arisanensis Hayata. The new compound was characterized by spectral methods and chemical reactions. The antiplatelet effects of isovitexin 6"-O-glucoside (1), isoorientin (2), 2 peracetate (3), isovitexin (4), luteolin 7-O-beta-D-glucoside (5), luteolin (6), isoorientin 6"-O-glucoside (7), and 7 peracetate (8) were studied using washed rabbit platelets. Of the compounds tested, 6 showed potent antiplatelet effects on arachidonic acid (AA)-induced platelet aggregation (IC50 = 43.5 microM). The effect of 2, 5, and 6 on the contraction of rat thoracic aorta was also studied. Compound 6 depressed markedly the contraction induced by Ca2+ (1.9 mM) in high-K+ (80 mM) medium, with an IC50 of about 156 microM and also inhibited noradrenaline (3 microM)-induced phasic and tonic contractions, with an IC50 of about 68 and 72 microM, respectively.

Synthesis and antithrombotic effect of xanthone derivatives.

A series of xanthone derivatives was synthesized and tested in-vitro for their ability to inhibit aggregation of rabbit washed platelets and human platelet-rich plasma (PRP) induced by various inducers. 2-Prenyloxyxanthone showed the most potent inhibition of rabbit washed platelet aggregation induced by arachidonic acid (1C50 = 10.2 microM). Of the compounds tested in human PRP, 2-[3 (propylamino)-2-hydroxypropoxy]xanthone (4) hydrochloride salt exhibited the most potent inhibition of platelet aggregation induced by adrenaline (IC50 = 4.4 microM), whereas in evaluation of mouse antithrombotic activity, compound 4 exhibited the most potent protection of mice from thrombotic challenge. Compound 4, 2-[3-(isopropylamino)-2-hydroxypropoxylxanthone hydrochloride salt and 2,5 dihydroxyxanthone suppressed the secondary aggregation induced by adrenaline in human PRP. We conclude that the antiplatelet effects of these compounds are mainly due to an inhibitory effect on thromboxane formation.

Synthesis and anti-inflammatory effects of xanthone derivatives.

Eighteen synthetic xanthone derivatives were tested for their inhibitory effects on the activation of mast cells and neutrophils. 1,3- and 3,5-Dihydroxyxanthone showed strong inhibitory effects on the release of beta-glucuronidase and histamine from rat peritoneal mast cells stimulated with compound 48/80. 1,6-Dihydroxyxanthone and 1,3,8-trihydroxyxanthone showed strong inhibitory effects on the release of beta-glucuronidase, and beta-glucuronidase and lysozyme, respectively, from rat neutrophils stimulated with formyl-Met-Leu-Phe (fMLP). 1,3- and 1,6-Dihydroxyxanthone, 1,3,7-trihydroxyxanthone, and 1,3,5,6-, 2,3,6,7-, and 3,4,5,6-tetrahydroxyxanthone showed potent inhibitory effects on superoxide formation of rat neutrophils stimulated with fMLP. 1,6- and 3,5-Dihydroxyxanthone showed remarkable inhibitory effects on hind-paw oedema induced by polymyxin B in normal as well as in adrenalectomized mice. These data indicated that the anti-inflammatory effect of these compounds is mediated through the suppression of chemical mediators released from mast cell and neutrophil degranulation.

Antiplatelet constituents of formosan Rubia akane.

A known steroid, in addition to triterpenoids, anthraquinones, naphthalenes and a new anthraquinone glycoside, xanthopurpurin 3-O-beta-D-glucoside, were isolated from the roots of Rubia akane grown in Taiwan. Mollugin, a naphthohydroquinone, showed strong inhibition of arachidonic acid (AA)-induced and collagen-induced platelet aggregation. In contrast, 2-methyl-1,3,6-trihydroxyl-9,10-anthraquinone, xanthopurpurin 3-O-beta-D-glucoside, and xanthopurpurin showed mainly strong inhibition of collagen-induced platelet aggregation.

Frangulin B, an antagonist of collagen-induced platelet aggregation and adhesion, isolated from Rhamnus formosana.

Emodin and its glycoside frangulin B were isolated from the plant Rhamnus formosana. Emodin inhibited the aggregation of rabbit platelets induced by arachidonic acid and collagen, without affecting that by ADP or PAF, while emodin acetate had no any antiplatelet effect. Frangulin B inhibited selectively and concentration-dependently collagen-induced aggregation and ATP release in rabbit platelets, without affecting those induced by arachidonic acid, ADP, PAF and thrombin. Frangulin B also inhibited the platelet aggregation induced by trimucytin which was reported to be a collagen receptor agonist isolated from Trimeresurus muscrosquamatus snake venom. The aggregability of platelets inhibited by frangulin B could be recovered after washing the platelets. Frangulin B also selectively suppressed the thromboxane B2 formation caused by collagen, but not those by arachidonic acid and thrombin. Similarly, the formation of inositol phosphate caused by collagen was also suppressed by frangulin B, while that of PAF or thrombin was not affected. In the presence of PGE1, frangulin B also decreased Mg(2+)-dependent platelet adhesion to collagen. It is concluded that frangulin B may be an antagonist of collagen receptor in platelet membrane.

Antiplatelet effects and vasorelaxing action of some constituents of Formosan plants.

Various xanthones as well as quercetin have been shown to exhibit antiplatelet activity. A series of anthraquinones analogues structurally related to xanthones and a series of quercetin-related compounds were tested for their antiplatelet effects. Emodin, frangulin B, kaempferol tetraacetate, quercetin-3-O-galactoside octaacetate, rhamnazin triacetate, and rhamnetin tetraacetate were found to be potent antiplatelet agents, and 1,8-dihydroxy-6-methoxy-3-methylanthraquinone 8-O-rhamnosyl-(1-->2)-glucoside, rhamnustrioside undecaacetate, rutin decaacetate, and quercetin-3-O-(6-O-alpha-L-arabinopyranosyl)-beta-D-galactopyranos ide decaacetate showed significant antiplatelet effects. Quercetin showed vasorelaxing action in rat thoracic aorta.

Flavonol and anthraquinone glycosides from Rhamnus formosana.

Two new flavonol triglycosides, and a new anthraquinone glycoside, have been isolated from the roots of Rhamnus formosana. These compounds have been characterized as rhamnazin 3-O-[alpha-L-rhamopyranosyl(1----4)-alpha-L-rhamnopyranosyl(1----6 )]-beta-D-galactopyranoside (rhamnazin 3-isorhamninoside), rhamnocitrin 3-O-isorhamninoside and 1,6,8-trihydroxy-3-methylanthraquinone 1-O-rhamnosyl(1----2)glucoside, respectively.